Ignition of turbulent non-premixed flames

Development of a novel flamelet-based model to include preferential diffusion effects in autoignition of CH4/H2 flames

“…However, during the pre-ignition phase, hydrogen molecules and radicals are formed by chain branching reactions. Due to diffusion effects, these species diffuse away from the most reactive mixture fraction ζ M R [32], leading to a decreased reactivity at this location and an increased ignition delay. When non-unity Lewis numbers are applied, the diffusivity of these species (in particular) is enlarged leading to a longer ignition delay.…”

Design of synthetic EGR and simulation study of the effect of simplified formulations on the ignition delay of isooctane and n-heptane

“…Although equivalence ratios of 2.5 can seem uninteresting for practical applications, it must be taken into account that autoignition occurs under rich local equivalence ratios in direct-injection diesel engines [45]. This concept is known as most reactive mixture f raction and it arises due to the balance of reactivities between the fuel-air ratio distribution and the temperature distribution.…”

Investigation of ignition process from visible to infrared by a high speed colour camera

“…The ignition of burner flames has been shown to be sensitive to ignition system [1], fuel flow rate and ignition location [2][3][4]. A good understanding of this process can be achieved through simultaneous multispectral time dependent visualisation of both the ignition physics and subsequent combustion.…”